1. Field of the Invention
The invention relates to a vehicle charging equipment for charging vehicles such as electric and hybrid vehicles.
2. Description of the Related Art
A vehicle charging equipment for charging vehicles such as electric and hybrid vehicles is known, which is provided with a charging equipment main body, a charging cable pulled out of the charging equipment main body and a charge connector which is attached to the tip of the charging cable and is to be fitted to a vehicle-side connector (charge port, inlet) provided on a vehicle.
For charging a vehicle using such a vehicle charging equipment, the charging cable is pulled out of the charging equipment main body and the charge connector is fitted (connected) to the vehicle-side connector of the vehicle.
It is desirable that the charge connector and the charging cable be put back into the original state (i.e., the state in which the charging cable is wound-up and stored in the charging equipment main body and the charge connector is arranged in the vicinity of the charging equipment main body) after finishing charging but it is not always retracted properly.
Especially in public parking spaces, a large number of unspecified vehicles frequently come in and out and charging cables of vehicle charging equipments provided in such places thus may be left uncared-for in the pulled-out state without being retracted properly.
In such a case, the charge connector or charging cable which are left uncared-for may be run over and damaged by in-coming vehicles or pedestrians may trip over such a charging cable, etc., and get injured. Furthermore, when the vehicle charging equipment is adapted to be provided on each pallet of mechanical parking facility, the charging cable hanging down from the pallet may get stuck and damaged in a carriage rail, etc., when the pallet moves, which is very dangerous. Therefore, the charge connector and the charging cable are desired to be automatically retracted after finishing charging.
In order to automatically retract the charge connector and the charging cable, removal of the charge connector from the vehicle-side connector needs to be detected in the charging equipment main body which is provided with a winding-up device for winding up the charging cable, and it is thus necessary to provide a fit determination means to determine whether or not the both connectors are fitted to each other.
In SAE J1772 (trademark, herein referred to as J1772 standard) defined by the Society of Automotive Engineers (SAE) and IEC 62196 part 3 (herein referred to as 62196 standard) defined by International Electrotechnical Commission (IEC), a means for determining whether or not the charge connector is fitted to the vehicle-side connector is preliminarily provided.
In detail, as shown in FIG. 7, a charge connector 71 conforming to the J1772 standard is provided with five terminals: two AC power source terminals 71a and 71b (neutral lines) through which AC power signals are transmitted; a ground terminal 71c to be a frame ground; and two signal terminals 71d and 71e. A vehicle-side connector 73 is provided with terminals 73a to 73e which respectively correspond to the terminals 71a to 71e of the charge connector 71. Meanwhile, in the 62196 standard, two more AC power source terminals are further provided in addition to the five terminals and are used together with the AC power source terminal 71a to supply three-phase AC power.
In the J1772 standard as well as in the 62196 standard, DC voltage (+12V) is applied to the signal terminal 71d from a controller 72a of a charging equipment main body 72 via a resistor R1 and the controller 72a monitors voltage (potential) of the signal terminal 71d. When the charge connector 71 is fitted to the vehicle-side connector 73, the signal terminal 71d is electrically connected to the signal terminal 73d of the vehicle-side connector 73 and is grounded via a resistive circuit 74 formed on a vehicle 75, which forms a closed loop and causes variation in voltage of the signal terminal 71d. In the J1772 standard, the voltage of the signal terminal 71d is detected by the controller 72a and fitting of the two connectors 71 and 73 is determined based on the detected voltage.
The signal terminal 71e of the charge connector 71 is used for detecting depression of a release button which is provided on the charge connector 71.
The release button is provided integrally with a locking mechanism such as latch for locking to the vehicle 75 when the two connectors 71 and 73 are fitted to each other, and it is configured such that the locking mechanism is released by pressing the release button and the fitting of the two connectors 71 and 73 is then released. Since the release button is always pressed when removing the charge connector 71 from the vehicle-side connector 73, detecting the depression of the release button allows disengagement of the two connectors 71 and 73 to be detected beforehand and charging current to be promptly reduced. As a result, it is possible to significantly reduce, e.g., damage on charging devices such as storage batteries caused by transient impact due to current interruption during charging large current, or burnout of a contact due to spark discharge caused by turning off a relay circuit while power is on.
A release button circuit 76 is provided with a switch SW opened by pressing the release button and two resistors R2 and R3, and is configured such that one end of the switch SW is connected to the signal terminal 71e, another end of the switch SW is connected to the ground terminal 71c via the resistor R2 and then the resistor R3 is connected in parallel to the switch SW. In a conventional vehicle charging equipment 70, the release button circuit 76 is completed within the charge connector 71 and a circuit, etc., related to the release button is not provided in the charging equipment main body 72. The charge connector 71 and the charging equipment main body 72 are connected via a four-core charging cable 77.
In vehicle 75, voltage is applied to the signal terminal 73e from a DC power source 78 via a resistor R4 and voltage of the signal terminal 73e is monitored. When the two connectors 71 and 73 are fitted to each other, the signal terminal 73e is electrically connected to the signal terminal 71e of the charge connector 71 and voltage is then applied to the release button circuit 76. In the release button circuit 76, the switch SW is closed and the resistor R3 is shorted when the release button is not pressed, but once the release button is pressed, the switch SW is opened and the resistor R3 is inserted. Accordingly, a resistance value from the signal terminal 73e up to the frame ground (a combined resistance value of the release button circuit 76 and a resistor R5) varies due to depression of the release button and voltage of the signal terminal 73e thus varies. Therefore, it is possible to detect depression of the release button by detecting variation in voltage of the signal terminal 73e on the vehicle 75 side.
Such a mechanism for detecting depression of the release button is essential to prevent damage on charging equipment in vehicle and is widely adopted, not just for the J1772 standard and the 62196 standard.
The related arts to the invention may be JP-A-2010-222793, JP-A-2011-063944 and JP-A-2011-111805.